Protocol for the Derivation of Environmental and Human ... - CCME

Appendix B
not exceed the background food exposure from the multi-media assessment by more than 20% of the
residual (TDI-EDI).
Where:
T AG = T R + I p + I b + I m [13]
T AG
= estimate of total contaminant intake from food produced on a remediated agricultural
site and off-site
Residential
The calculation of exposure by local produce consumption (food check) for a residential setting has to
be added to the generic guidelines. Guidelines taking into account contribution of local food produce to
the total intake of contaminant will appear in the assessment document available for each substance
studied by the Subcommittee.
Equations (state their numbers) are slightly altered for the residential scenario. The Subcommittee has
proposed that 10% of garden produce will be grown on-site, and no meat or milk will be of local origin.
Therefore, Equation 12 is modified under these conditions to remove only the background exposure to
produce, and becomes:
T R = T F - I BP [14]
The new estimate of contaminant intake from food sources at a residential site will be equal to the
addition of the estimated intake from on-site and off-site produce to the remainder (T R ).
Where:
T RES = T R + I p [15]
T RES = estimate of total contaminant intake from food produced on a remediated residential site
and off-site
If T RES is greater than the background food exposure by more than 20% of the residual (TDI-EDI), the
Subcommittee is recommending that the contaminant exposure from backyard produce be evaluated on
a site-specific basis, as the percentage of home grown produce is highly variable.
4.2 Carcinogens
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